If you have ever been in a situation where you are running a large delete (or update) on a table, and need to know the progress there is a way you can find out.
The way I do it is open a new window and run
Select 1 from <tablename> (NOLOCK) WHERE <your filter>
This will then give you all the rows in their uncommitted state, you can then predict fairly accurately how long a big delete is going to take, by comparing the row counts over a time period.
Then when your boss is breathing down your neck wanting to know how long the database is going to be down for you can say approximately 6 hours, instead of saying you have no idea!